Atmospheric water vapor is problematic in many situations. This is particularly so in situations combining high humidity with close or closed environments such as crowded rooms or closets; the presence of hydrophilic materials; and intermittently opened containers of organic liquids such as gasoline. Some of the problems high humidity can cause are caking of dried powder and granular substances, increase growth of mildew and fungi, corrosion of metal surfaces, and water contamination of organic liquids (especially internal combustion engine fuels). A variety of solutions have evolved or been developed in the field to address these problem situations.
Trapped water can be a source of corrosion in a high humidity environment. A solution to this situation is suggested by Walley et al., U.S. Pat. No. 4,588,505. Walley et al. provide a weighted, open mesh pouch containing a water absorbent to be placed at the bottom of, for example, a gasoline drum. This device absorbs water only from a liquid phase but does not prevent the initial water contamination from forming.
Mayeaux, U.S. Pat. No. 5,324,448, suggests a packet including a composition combining a desiccant and a vaporous corrosion inhibitor for use where corrosion is caused by atmospheric humidity in electronic components. Some powders and granules (salt, sugar, amino acids, etc.) can cake or form clumps when exposed to high humidity. A number of additives are know in the art for preventing such caking or clumping, such as aluminum silicate in table salt. Kaneko et al, U.S. Pat. No. 5,657,866, provide a "double bag" packaging system comprising inner water permeable and outer water impermeable liners holding a desiccant between them.
Yeager, U.S. Pat. No. 5,660,868, teaches a dual compartment food storage bag with one compartment containing a soaker pad for absorbing liquids and the other compartment for containing food. The overall bag is sealable, but the two compartments communicate by means of perforations in a shared compartment wall between them.
The above technologies have the limitation that the desiccants they use cannot be deliquescent. A deliquescent composition is one that melts away or dissolves gradually and becomes a liquid by attracting and absorbing moisture from the air. If a deliquescent composition were used in the above situations, the resultant liquid would itself be a contaminant. Further, because deliquescent derived liquids contain chemicals and have chemical properties different from pure water, in the case of contact with food, they could be toxic.
In high humidity situations, involving relatively close or closed environment such as a clothes or storage closet, camper or similar space, the relatively high water vapor extraction capabilities of a deliquescent is more desirable than other types of desiccants. Deliquescents have been used for such applications. Cullen, U.S. Pat. No. 5,148,613, discloses a closet drier in a bucket conformation, having upper and lower compartments and an open top covered with a gas permeable membrane. The Cullen device is an open container and must be placed on the floor or some other surface.
It would be desirable to have an easily disposable, non-spillable dehumidifying pouch, preferably composed of inexpensive materials. What is also needed is a non-spillable pouch that can be hung in a closet or storage area so that clothes or articles that need to be dry will not be accidentally contaminated by the dehumidifying and deodorizing pouch.